When multiple players wish to use their Object Powers at the same time during the Power Phase, it is up to the Leader to determine who declared first. Since the Leader is also on a team (Kids or Neighbors) they should be careful to be fair and impartial. However if your group is having trouble with this rule, you may use this option rule to help determine the order that powers are used.
Place the Game Box in a common space in the middle of the play area, in reach of all players.
In addition to players declaring they want to use their power out loud, they must also place their hand on the Game Box. The first player to do so may use their power first.